Structural characterisation of self-implanted Si after HT-HP treatment

Abstract

Recovery of damages in implanted silicon is still not fully understood. In this work, self-implanted silicon Si:Si is a model material. The implantation-damaged area in Si:Si is under high quasi-hydrostatic stress. Therefore, the application of external hydrostatic pressure (HP) at annealing of Si:Si samples gives possibility to obtain valuable information on the stress-related effects during out-annealing of structural damages. Czochralski grown single crystalline silicon (Cz-Si) samples were subjected to the implantation with Si + ions (silicon dose D = 5 × 10 16 cm −2) at 160 keV energy ( E). The Si:Si samples were treated at a high temperature (HT) up to 1130 °C under hydrostatic argon pressure up to 1.1 GPa for 5 h. Changes in the dielectric function ( ɛ) in both the as-implanted and HT-HP treated silicon samples have been determined. The considerable amelioration of both optical and structural properties of the self-implanted silicon samples for such treatment conditions like pressure, p = 1.1 Gpa; temperature, T = 800 °C; time, t = 5 h has been observed. For samples treated under 1.1 GPa and for 5 h, both real part ( ɛ 1) and imaginary part ( ɛ 2) of dielectric constant decreased with the increase of temperature in all spectral range. The agreement between results obtained by spectroscopic ellipsometry (SE) and other optical techniques has been found.